Circular economy: live larvae recycling organic waste as sustainable feed for rural poultry

FAO has identified insects as an innovative, alternative and sustainable source of nutrients for animal feed. The insect production system represents an efficient Circular Economy model. Insects are biotransformers of organic waste (which most of time represents a production cost for the agro-industry) into high quality nutrients to be reused. Live insect larvae are suitable to be directly administered as feed ingredient to poultry and are also suggested to play a positive general effect on bird health and welfare. In a Circular Economy perspective, the insect rearing residues (insect frass) may find use as an organic fertilizer. Preliminary researches also indicated that an energetic valorisation (aerobic and anaerobic processes) is feasible but all these aspects needs to be deeper investigated. Hermetia illucens (BSF) is the best insect candidate to be used for animal feed purposes. A variety of organic waste ingredients can be potentially used as substrates for BSF larvae rearing, but their relative impact on the growth performance, chemical composition, microbiological safety and waste reduction efficiency of the larvae is still largely unknown. The available knowledge on the nutrient requirements of BSF larvae is also very scant. Optimized diets based on mixtures of organic waste ingredients, as well as targeted feed formulae based on specific protein and carbohydrates contents, still have to be clearly defined. As far as poultry production is concerned, insects represent one of the most promising alternative source of nutrients and recent researches have shown great potential environmental benefits of rearing insects for poultry feed. While in European Community the use of insect processed proteins is under discussion but still not permitted for poultry feeds, the Reg. (EU) 2017/1017 allowed the use of live larvae in livestock feeding. Live larvae fed to poultry provide good nutrients (proteins, amino acids, energy, minerals, vitamins) and bioactive compounds with positive effects on health, but also enable to express their normal behaviour (i.e., foraging activity), with expected positive impacts on animal welfare and product quality. Nevertheless, data on these aspects are still missing and researches are needed. Following a multidisciplinary and sustainable approach, the CELLOW-FeeP project intends to fill the above-mentioned gap of knowledge directly involving the societal actors and trying to align both the project processes and outcomes with the values, needs and expectations of the European society. The aims of the project are: i) to identify nutrient requirements of BSF larvae, to optimize their diet and to define targeted feed formulae by using mixtures of available organic waste ingredients ii) to valorise the agronomic and energetic potential of the frass derived from BSF larvae rearing iii) to identify optimal inclusion levels of live BSF larvae (in substitution of a conventional protein source) into diets destined to slow-growing chickens, based on the growth and slaughtering performances, health, welfare and meat quality of the birds iv) to assess the role of BSF larvae bioactive compounds (i.e., lauric acid, chitin, anti-microbial peptides) on health-related parameters of chickens by means of innovative metagenomics methodologies v) to actively involve young researchers in technical and dissemination aspects of the project, contributing to their education and training also increasing their competitiveness at job market national and international levels vi) to enhance public knowledge, awareness, sensitiveness and active participation towards environmental and economic issues of current worldwide relevance, in compliance with the EU legislation on Circular Economy. The following results are expected: i) specific diet compositions for BSF larvae production ii) forecast of the proportional reduction of organic waste materials and, consequently, optimization of o